Crankcase ventilator



April 11, 1961 w. ZUBRO CRANKCASE VENTILATOR Filed Aug. 7, 1959 IN V EN TOR. 14 4/24 r Z2127.

# FIVE/ United States CRANKCASE VENTILATOR Walter Zubro, Racine, Wis., assignor to Walker Manufacturing Company, Racine, Wis, a corporation of Delaware Filed Aug. 7, 1959, Ser. No. 832,306 Claims. 01. 121- 194 This invention relates to an improved crankcase ventilator for an internal combustion engine.

Many types of internal combustion engines require that the crankcase thereof be maintained at approximately atmospheric pressure. A simple aperture in the crankcase wall is unsatisfactory as a venting means because such internal combustion engines often employ the crankcase as an oil sump thereby requiring that the venting means he bafiied to restrict the passage of oil fumes outwardly from the crankcase. Further, because the air mass within the crankcase is continuously pulsating at a frequency di rectly proportional to the speed of the engine, the baffling is preferably orientated so as to muffle pulsations.

Accordingly, one object of the present invention is to provide an improved ventilator for maintaining the crankcase of an internal combustion engine at atmospheric pressure. 4

Another object is to provide a crankcase ventilator in accordance with the above object that restricts fluid flow between the crankcase and the atmosphere.

Another object is to provide a crankcase ventilator that effectively disperses and mutfles pulsations emanating from within the crankcase.

Another object is to provide a crankcase ventilator that is relatively simple in construction and contains a minimum number of parts.

Other objects and advantages of the present invention will become more apparent from the following description wherein reference is made to the drawings, in which:

Figure 1 is a side elevation of a crankcase ventilator, shown in operative association with an internal combustion engine;

Fig. 2 is a cross-sectional view taken along the line 2-2 of Fig. l, enlarged for clarity;

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Fig. 2; and

Fig. 4 is a cross-sectional view of an end closure for the ventilator.

Referring to the drawings, an exemplary embodiment of a crankcase ventilator in accordance with the present invention is shown in operative association with an internal combustion engine 11. The details of the engine 11 form no part of thepresent invention and it will be obvious that the crankcase ventilator 10 is capable of utilization with other types of internal combustion engines.

In the embodiment illustrated in Fig. 1, the crankcase ventilator 10 is mounted on top of the engine 11 and extends downwardly into a crankcase 12 thereof through an aperture 13 (Fig. 2) in an upper wall 14 of the crankcase 12. A suitable gasket 15 is provided within the aperture 13 between the upper wall 14 of the crankcase 12 and the ventilator 10 to seal the aperture 13 against the passage of oil fumes. The ventilator 10 is preferably removable from the aperture 13 to provide for the admission of oil into the crankcase 12 of the engine 11.

The crankcase ventilator 10 comprises an elongated tubular body member 18 having a necked-down portion 19 at the lower end thereof that is acceptable within the aperture 13 in the crankcase 12. The body member 18 has an aperture 20 near the upper end thereof for communication with a transversely extending vent pipe 21 that is secured to the body member 18 as by welding. The vent pipe 21 has an end portion 22 that is folded downwardly so as to conduct any oil fumes that escape through the ventilator 10 outwardly of the engine compartment (not shown). The body member 18 is closed at an upper end 24 thereof by an end closure 25 of stepped cup-shaped configuration. The end closure has a bottom wall 26, an axially extending side wall 28 that is folded at a re-entrant angle to define an annular recess 29, a transverse section 30 that extends radially outwardly from the recess 29, an outer axially extending wall 31 and a radially outwardly extending flange 32 at the upper end thereof. The outer side wall 31 of the end closure 25 is acceptable within the end portion 24- of the body member 18 in nesting relationship and the radially outwardly extending flange 32 is foldable over the upper end portion 24 of the body member 18 (Fig. 1) to secure the end closure 25 t0 the tubular member 18.

The ventilator 10 has an inner tube 34 that extends between the end closure 25 and the necked-down portion 19 of the body member 18. The inner tube 34 is accepted within the necked-down portion 19 in telescoping relation and is positioned by a lip 35 on the lower end of the necked-down portion 19 of the body member 18. The inner tube 34 accepts the side wall 28 of the end closure 25 in nesting relation and extends into the recess 29 thereof to positively locate the tube 34 with respect to the body member 18.

The inner tube 34 has a plurality of spaced apertures 36, of relatively small cross-sectional area, disposed at the opposite side thereof from the aperture 20 in the body member 18. The apertures 36 restrict the flow of oil fumes outwardly of the crankcase 12, but are sufliciently large to preclude the creation of a pressure differential between the crankcase 12 and the outside atmosphere. Oil fumes that flow upwardly from the crankcase 12 through the inner tube 34 must pass radially outwardly through the apertures 36 in the tube, then around the inner tube 34 and out the aperture 20 in the body member 18, then outwardly through the vent pipe 21. This serpentine path effectively restricts passage of the fumes outwardly of the crankcase. Also, the serpentine path through the ventilator 10 eifectively mufiies and disperses any air pulsations emanating within the crankcase 12.

From the foregoing description it should be obvious that the ventilator 10 is of relatively simple construction, yet provides an effective means for ventilating the crankcase of an internal combustion engine and for restricting the flow of fumes and noise outwardly of the crankcase.

While it will be apparent that the embodiments of the invention herein disclosed are well calculated to fulfill the objects of the invention, it will be appreciated that the invention is susceptible to modification, variation and change Without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

l. A crankcase ventilator comprising a tubular body member having a necked-down portion at one end thereof, a closure member sealably closing said body member at the other end thereof, an inner tube having a vent means extending between and sealably secured to said closure member and within said necked-down portion and defining an annular chamber within said body member, said body member having an aperture therein, and a vent tube secured to said body member and communicating with said aperture and said vent means to restrict fluid flow outwardly of said crankcase and maintain said crankcase at approximately atmospheric pressure.

2. A crankcase ventilator comprising a tubular body Patented Apr. 11, 1961 member having a necked-down portion at one end thereof, a closure member having an axially extending portion sealably secured to said body member at the other end thereof, an inner tube extending between and supported radially and axially with respect to said body member by said axial portion of said closure member and said neckeddown portion, said body member having an aperture communicating with an outwardly extending vent tube, and vent means in said inner tube communicating with said aperture in said housing to vent said crankcase to the atmosphere.

3. A crankcase ventilator comprising a tubular body member having an end portion of reduced diameter, a closure member sealably secured to said body member at the other end thereof, an inner tube having an aperture therein extending between and supported by said closure member and the reduced end portion of said body member and defining an annular chamber within said body member, and a vent tube connected to said body member and communicating with said annular chamber for maintaining said chamber and the crankcase at atmospheric pressure.

4. A crankcase ventilator comprising a tubular body member having a necked-down portion at one end and a closure member sealably secured to the other end thereof, an inner tube extending between and supported by said closure member and said necked-down portion of the body member defining an annular chamber within said body member and having an open end portion extending through said necked-down portion for communication with the crankcase, said inner tube having a plurality of relatively small apertures communicating with said chamber and said body member having a relatively large aperture communicating with said chamber, and a vent tube secured to said body member and communicating with the large aperture therein whereby the crankcase is vented to the outside atmosphere.

5. A crankcase ventilator comprising a tubular body member having a necked-down portion at one end and a closure member at the other end thereof, an inner tube having an open end extending into said necked-down portion in close telescoping relation for communication with the interior of a crankcase, the other end of said inner tube being supported and closed by said closure member, said inner tube defining an annular chamber within said body member and having a vent means communicating with said chamber, said body member having means c0mmunicating with said chamber and the atmosphere extern-ally of said crankcase whereby fluid flow outwardly of said crankcase is restricted while said crankcase is maintained at atmospheric pressure.

References Cited in the file of this patent UNITED STATES PATENTS 1,906,663 Taylor et al May 2, 1933 1,960,657 Alexander May 29, 1934 2,821,174 Scheiterlein Jan. 28, 1958 

